Generally, methods of constructing retaining wall structures include a slurry wall method, a soil cement wall (SCW) method, a concrete in-situ pile (CIP) method, a sheet pile method, and the like. Among the aforementioned methods, other methods except the slurry wall method are methods of constructing temporary retaining wall structures that not only become obstacles when a variety of construction materials are moved or unloaded, concrete is poured, or a building lot is dug, but also should be installed, dismantled or moved through processes separate from main construction works, thereby increasing construction costs and prolonging a construction period.
In this regard, there has been recently used the slurry wall method, which is a method of constructing a permanent retaining wall that will be utilized as foundations and an outer wall structure of a construction. However, the slurry wall method of constructing a permanent retaining wall has problems in that a lot of construction equipment is required and construction costs increase in constructing the retaining wall. To solve these problems, the applicant filed a Korean utility model application (corresponding to Korean Utility Model Registration No. 20-0313739) entitled “Retaining wall structure using PHC pile”, which discloses a novel method of constructing a permanent retaining wall structure, wherein construction costs are reduced and construction processes are simplified.
The method of constructing a permanent retaining wall structure disclosed in the Utility Model Registration entitled “Retaining wall structure using PHC pile” is characterized in that a PHC pile 100 comprises a hollow 102 formed at the center thereof, and a female steel connector 106 and a male steel connector 104 embedded at opposite sides of a periphery thereof, so that a plurality of PHC piles can be connected to one another by means of the female and male steel connectors 106 and 104, as shown in FIG. 1.
In the method of constructing a permanent retaining wall structure using the PHC pile, however, there is inconvenience in that the female and male steel connectors 106 and 104 should be connected by means of iron reinforcing rods upon construction of a retaining wall structure by interconnecting PHC piles to one another. This cannot meet the intention of manufacture of a PHC pile that should be mass-produced in a factory. Further, since the male steel connector 104 of the PHC pile 100 is made to protrude, there are problems in that the protruding portion of the male steel connector may be very likely to be damaged during curing or movement of the PHC pile, whereby the male steel connector may not be suitable for connection of retaining walls which requires accurate dimensions thereof.